Ciceeo e



(No Model.)

- O. R. 0. FRENCH.

REAMER.

No. 280,368; Patented July 3, 1883.

UNITED STATES PATENT OFFICE.

CIOERO R. O. FRENCH, OF PROVIDENCE, RHODE ISLAND.

REAMER.

SPECIFICATION forming part of Letters Patent No. 280,368, dated July 3,1883. Application filed January 13, 1883. (No model.)

To on whom it may concern.-

Be it known that I, OIOERO R. O. FRENoH, of the city and county ofProvidence, in the State of Rhode Island, have made certain new anduseful Improvements in Reamers, of which the following is a full andcorrect description, reference being had to the accompanying drawings,forming a part of this specification.

This invention consists in making a reamer with a slot extending throughthe cutting part and putting stay-screws through the two parts dividedby the slot to hold them together,-.

and in putting taper screws in the slot to sep arate the two parts, sothat the size of the reamer may be increased or diminished for thepurpose of adjusting it to an exact size.

In the drawings, Figure l is a side view of the reamer in the directionof the slot. Fig. 2 shows the reamer turned one-quarter way round. Fig.3 is a longitudinal section taken through the plane of the slot. Fig. 4shows the same with long taper screws. Fig. 5 is the same with adifferent arrangement of the screws. Fig. 6 shows a cross-section takenthrough the line as x, Fig. 1.

A is the upper part or body of the reamer. B is the cutting part, whichis fluted in any of the usual ways, so as to form cutting-edges. A slot,t, is made through the center of the reamer, that extends through thecutting part B and well up toward the upper end of the reamer. Twostay-screws, b b, are put through the two parts of the reamertransversely to the slot t, one near each end of the fluted ortion, todraw the two halves together. T ese screws 7) b are fitted to turnfreely without threads in that part of the reamer next to the screw-headand with screw-threads in the other part of the reamer. Short taperscrews a a and a a are fitted with screw-threads into taper holes, thatintersect the slot 15 on both sides of the reamer and near thestay-screws b b, so that when they are turned in they will separate thetwo halves of the reamer and enlarge its size.

In Fig. 4: are shown two long taper screws, a a, each one taking theplace of two of the short screws or a in Fig. 3. These longer screws arefitted into their taper holes with screw-threads their whole length, sothat they shall have a bearing both sides of the center or entirelythrough the reamer.

Fig. 5 shows the two short screws a (1 inserted in the end of thereamer, one each side of the stay-screw, instead of being put in thesides, as above described, but producing the same effect in the sameway-that is, expanding the reamer by separating the two parts whenscrewed in.

The operation is as follows: By loosening the stay-screws b b andscrewing in the taper screws a a or a a or au o the size of the. reamerwill be increased by the separation of the two halves, and, vice versa,by loosening the taper screws and turning in the stay-screws b b thesize of the reamer will be decreased by the drawing together of thehalves; and by operating the screws at either end separately the reamermay be made to taper in either direction or its sides made perfectlyparallel.

Having thus described my improvement, what I claim as my invention, anddesire to secure by Letters Patent, is-

As a new article of manufacture, a reamer constructed substantially asherein shown and described-that is, with a slot extending lengthwise andcentrally through the cutting part, and having taper screws inserted inthe slot to separate the parts, and transverse stayscrews to hold themtogethersubstantially as set forth.

oionno R. o. FRENCH.

Witnesses:

FRANK. BULLwENr, FERDINAND O. FRENCH.

